The invention relates to a device for the creation of a precise working portal for arthroscopic surgery, endoscopic surgery or other surgical procedures using the aid of video technology to visualize internal anatomical structures. As minimally invasive surgery has evolved, numerous tools have been developed to assist in treating medical conditions that have previously been treated with open and more invasive techniques. Arthroscopic surgery of the knee is a common example of this surgery. Typically, the first step in arthroscopic surgery is to create a portal for the camera. This "blind" portal is made by palpating known anatomical structures near the desired location of the portal and making an incision. The camera is placed through this portal and the knee is inflated with fluid. Typically, next a spinal needle is percutaneously directed toward the area of pathology to identify the correct location of a "working" portal. The working portal will provide access for future instruments to be passed. A knife blade is then passed into the joint to approximate the plane of the needle. This approximation can lead to several problems. The knife can pass on a different plane, causing injury to vital structures. The knife blade can pass in a different plane, making placements of instruments difficult. Finally, if the knife blade does not pass completely into the joint, it can leave a tighter working portal which makes passing instruments more difficult as they get caught up in fat and synovium that lines the joint.
Other persons have attempted to design devices that would create an accurate portal. For example, U.S. Pat. No. 5,120,318 discloses a portal maker with a puncturing tool and a cannulated shaft having a circular cross section. The puncturing tool is hollow so it can accept a wire rod passing inside of it during one step of a disclosed procedure. U.S. Pat. No. 4,790,312 discloses a surgical instrument for operating percutaneously in a living body. It has a hollow handle and a an elongated shaft of circular cross section.
There is no single surgical instrument in the prior art that is able to successfully and accurately identify the proper location for and then make an unlined working portal in that exact location in a living being for preparation of arthroscopic or endoscopic surgery.